Broadband noise is generated when turbulence in the wake of a rotor impinges on a downstream stator. Theory for this process is derived giving the sound power spectrum in terms of the 3 dimensional wavenumber spectrum of the turbulence. The turbulence inhomogeneity related to blade-to-blade variations and variations across the span of the vanes is included rigorously in the analysis. Relationships between the turbulence spectrum and the cascade response spectrum are discussed in detail. Calculations for a model fan verify correct behavior of the noise equations. A parametric study is presented with variations in vane count, solidity, Mach number, stagger angle, and turbulence scale.
Turbulence/cascade interaction: spectra of inflow, cascade response, and noise
Turbulenz/Kaskaden-Wechselwirkung: Einlaufströmungs-, Kaskaden- und Lärmspektren
1998
13 Seiten, 15 Bilder, 7 Quellen
Conference paper
English
AN ANALYTICAL MODEL FOR THE PREDICTION OF AIRFOIL CASCADE-TURBULENCE INTERACTION NOISE
British Library Conference Proceedings | 2019
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